2020-01-10 09:47:50

by Gerd Hoffmann

Subject: [PATCH] drm/virtio: add missing virtio_gpu_array_lock_resv call

When submitting a fenced command we must lock the object reservations
because virtio_gpu_queue_fenced_ctrl_buffer() unlocks after adding the
fence.

Reported-by: Jann Horn <[email protected]>
Signed-off-by: Gerd Hoffmann <[email protected]>
---
drivers/gpu/drm/virtio/virtgpu_plane.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/virtio/virtgpu_plane.c b/drivers/gpu/drm/virtio/virtgpu_plane.c
index 390524143139..1635a9ff4794 100644
--- a/drivers/gpu/drm/virtio/virtgpu_plane.c
+++ b/drivers/gpu/drm/virtio/virtgpu_plane.c
@@ -232,6 +232,7 @@ static void virtio_gpu_cursor_plane_update(struct drm_plane *plane,
if (!objs)
return;
virtio_gpu_array_add_obj(objs, vgfb->base.obj[0]);
+ virtio_gpu_array_lock_resv(objs);
virtio_gpu_cmd_transfer_to_host_2d
(vgdev, 0,
plane->state->crtc_w,
--
2.18.1

2020-01-10 14:29:29

by Jann Horn

Subject: Re: [PATCH] drm/virtio: add missing virtio_gpu_array_lock_resv call

On Fri, Jan 10, 2020 at 10:45 AM Gerd Hoffmann <[email protected]> wrote:
> When submitting a fenced command we must lock the object reservations
> because virtio_gpu_queue_fenced_ctrl_buffer() unlocks after adding the
> fence.

Thanks a lot! With this patch applied, my VM doesn't throw lockdep
warnings anymore. If you want, you can add:

Tested-by: Jann Horn <[email protected]>

> Reported-by: Jann Horn <[email protected]>
> Signed-off-by: Gerd Hoffmann <[email protected]>
> ---
> drivers/gpu/drm/virtio/virtgpu_plane.c | 1 +
> 1 file changed, 1 insertion(+)

2020-01-10 21:03:48

by Chia-I Wu

Subject: Re: [PATCH] drm/virtio: add missing virtio_gpu_array_lock_resv call

On Fri, Jan 10, 2020 at 6:27 AM Jann Horn <[email protected]> wrote:
>
> On Fri, Jan 10, 2020 at 10:45 AM Gerd Hoffmann <[email protected]> wrote:
> > When submitting a fenced command we must lock the object reservations
> > because virtio_gpu_queue_fenced_ctrl_buffer() unlocks after adding the
> > fence.
>
> Thanks a lot! With this patch applied, my VM doesn't throw lockdep
> warnings anymore. If you want, you can add:
>
> Tested-by: Jann Horn <[email protected]>
>
> > Reported-by: Jann Horn <[email protected]>
> > Signed-off-by: Gerd Hoffmann <[email protected]>
Reviewed-by: Chia-I Wu <[email protected]>
> > ---
> > drivers/gpu/drm/virtio/virtgpu_plane.c | 1 +
> > 1 file changed, 1 insertion(+)